1. Technical Field
The present invention relates to apparatus and methods for analysis of whole blood samples in general, and for the determination of certain hemoglobin based parameters, such as hemoglobin concentration, of an unlysed, undiluted whole blood sample in particular.
2. Background Information
Physicians, veterinarians and scientists have examined human and animals' biologic fluids, especially blood, in order to determine constituent particulate quantities as well as to identify the presence of unusual particulates not seen in healthy subjects. The particulates generally measured, quantified and identified include red blood cells (RBCs), white blood cells (WBCs), and platelets. RBC analyses can include determinations of RBC number, hemoglobin concentration, and hematocrit (also referred to as the packed cell volume).
In many prior art applications, the hemoglobin concentration of a blood sample is determined by first lysing the RBCs within the sample, and subsequently determining the hemoglobin concentration of the sample containing the lysed RBCs. A distinct disadvantage of lysing the RBCs is that once the RBCs are lysed, it is no longer possible to perform cellular analyses on RBCs in the aforesaid sample; e.g., RBC cell volume (CV), mean cell volume (MCV), cell hemoglobin concentration (CHC), mean cell hemoglobin concentration (MCHC), mean cell hemoglobin content (MCH), etc.